Traditionally, most sports are based around able-bodied individuals. To play a given sport, a player customarily must have at least one functioning hand and both legs. The sport of bowling is no exception. A customary bowler usually has at least one functioning hand, and two functioning legs, allowing them to pick up a ball and throw the ball down the lane at the arrangement of pins at the far end of the lane.
As a result, prospective bowlers who are not able-bodied are at a distinct disadvantage to more able-bodied bowlers. If the prospective bowler lacks one or both functioning hands, a bowler cannot grasp or throw the ball with their hands. The prospective bowler without hands is left needing to awkwardly kick the ball down the lane. Given that the bowler's foot or shoe is more difficult to manipulate than a hand, a bowler without one or both hands has a difficult time accurately aiming the ball, meaning the handless bowler cannot compete effectively against more able-bodied players.